CERVICAL SPINAL STENOSIS

I HAVE A FRIEND'S MOTHER WHO HAS BEEN DIAGNOSISED WITH CERVICAL SPINAL STENOSIS. WHAT IS THIS, WHAT CAUSES IT AND HOW IS IT TREATED? CAN IT BE CURED? IS PHYSICAL THERAPY GOOD FOR IT? HER ARMS GET NUMB AND HER LEGS FEEL LIKE THEY ARE GOING OUT FROM UNDER HER.HER HANDS ARE BECOMING USELESS. ARE ALL THESE SYMPTOMS RELATED? WOULD CARPLE TUNNEL BE A SYMPTOM OR CONFUSED FOR THE SPINAL STENOSIS